The issue is that “BlueSky” is, for most of its users, the centralized official app. If that gets bought and starts blocking or demoting content from “non-official” clients, switching to a third-party client will not help you since you would lose your contacts.

And the longer this centralized situation lasts, the harder it will be to get back to a healthy ecosystem where nodes are truly peers and none of them can hijack the network on its own.

(Also, I am ignoring the complexity and cost of running an AppView. Running a Mastodon server is a $5/month affair, running a BlueSky AppView is several orders of magnitude more expensive.)